title: Pronuclei of Heliophrya erhardi Matthes during conjugation and their differential association with coated and uncoated microtubules.
abstract: Microtubules surrounding the pronuclei during conjugation of the suctorian ciliate Heliophrya erhardi can be divided into 2 distinct classes by electron microscopy. Microtubules around the stationary nucleus have a conventional appearance and presumably serve as a skeleton, anchoring that nucleus in its cytoplasmic position. Microtubules surrounding the prospective migratory nucleus are coated with electron-dense material and are in some cases associated with 7-nm filaments. These coated microtubules supposedly function to transport the migratory nucleus into the conjugation partner.
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000648:ultrastructure*; D016798:Ciliophora / Q000648:ultrastructure*; D003227:Conjugation, Genetic; D008854:Microscopy, Electron; D008858:Microscopy, Phase-Contrast; D008870:Microtubules / Q000648:ultrastructure*